Catalan Countries is a modern term to describe the lands where Catalan is the original language. Catalan is a romance language spoken by 7-9 million people. The Catalan Countries were part of the Aragon Crown, which in the 15th century included the Principality of Catalonia, the Kingdom of Majorca and the rest of the Balearic Islands, the Kingdoms of Valencia, Aragon and Naples, the islands of Sicily and Sardinia, and the Greek dukedoms of Athens and Neopatria.

Unlike most people believe, the marriage of the King Ferdinand II of Aragon and the Queen Isabella of Castile in 1479 (the Catholic Monarchs) did not unified all these kingdoms (as an example, after Isabella's death, Ferdinand was expelled from Castile.) In the 18th century, the remains of the Aragon Crown were military invaded by Castile (with the help of the French) and incorporated into Spain, abolishing its government institutions and laws, prohibiting public use of Catalan language for the first time with the Decret de Nova Planta (New Regime Decree); this decree has never been formally abolished.The Catalan Countries include Catalonia, Valencian Country, Balearic Islands, Andorra, a strip in east Aragon, North Catalonia (today part of France), and the Sardinian city of Alghero. In Catalan we call it Països Catalans, abbreviated as PPCC.